In a wireless digital network, such as a Wireless Fidelity (Wi-Fi) network operating in accordance with the IEEE 802.11n standard or the IEEE 80.211ac standard, several multiple-antenna techniques may be utilized to improve the capacity and the performance of the system. Such techniques may include spatial multiplexing and beamforming, etc.
The technique of spatial multiplexing exploits multipath propagation of Radio Frequency (RF) signals to improve the reliability of signals, thereby improving the signal-to-noise ratio (SNR). When the spatial multiplexing technique is utilized, for a given SNR, the spatial multiplexing gain and the ability to support higher multi-stream Modulation and Coding Scheme (MCS) depend on the ability of the receiver to reliably decode each spatial stream.
Techniques such as transmit beamforming (TxBF) are used to improve the SNR of specific clients. However, these techniques may reduce spatial multiplexing gain due to the reduction in transmit diversity.